In a fairly interesting article by Bob Beale discussing "personality" in animals and a comparison of such traits to their human counterparts, we got a chuckle from this passage:
"Likewise, scientists now recognise that many animals have 'personality', in that they display consistent differences in behaviours. Dr Biro believes it is significant that those behaviours often relate to the rates at which they acquire and expend energy through feeding or activity.
"Some of us are couch potatoes while others are drawn to sport and exercise," notes Dr Biro. "We often associate the athletic 'jock' type or person with being aggressive and social, whereas the more sedentary 'nerd' often is seen as more socially awkward and submissive."